The present invention relates to a method of elastifying a substrate blank and to an elastified substrate blank.
Elastic net or film has been used to elastify pants type articles, such as diapers, pant diapers, sanitary briefs, incontinance garments etc. GB-A 2 248 380 describes for example a method for elastifying a pants type disposable article, whereby elastic threads are laid out in alternating straight sections and curved sections corresponding to the leg portions. Separate transverse elastic portions are laid in the waist sections. In general this is a very complicated procedure involving a number of steps and which are prone to malfunctioning. Nor is it possible according to this known method to elastify an entire pants type article to hold it securely in place against the body of the wearer.
WO 93/18729 describes the application of net elastic strips in straight lines, longitudinally to elastify the leg openings and transversely to elastify the waist portions. This is simpler than the above method but the straight leg opening elastic strips do not conform well to the wearers legs when worn. As in the above case, such elastification requires both transverse and longitudinal laying of the strips and the entire pants type article is not elastified, only the end and side edge portions.